Pumping Stations. 133 



The pumping station for tlie North Reclamation was erected after 

 the scoop wheel had been in operation some time, and it was deter- 

 mined to adopt a centrifugal pump as the more effective machine 

 tinder all circumstances, its great advantage over the wheel being its 

 adaptability to varying Hfts and less cost of foundations. The pump 

 used was one of Appold's type, supplied by Messrs. Easton and Ander- 

 son. It is self-contained in a cast-iron frame, with galvanised iron 

 fan, 4 feet diameter by 15 inches deep, with diaphragm in middle 

 of its depth, and revolving in cast-iron case. Two suction pipes 

 conduct the water to above and below the fan, which is carried by 

 a vertical spindle making 133 revolutions a minute. Motion is given 

 to the spindle by a bevel pinion with 43 teeth geared into mortice 

 bevel fly-wheel, with 114 teeth keyed on to the crank shaft. The 

 pump is driven by a pair of direct-acting condensing engines, having 

 cylinders i8| inches diameter, with 2 feet stroke ; steam being used 

 at pressure of 50 lb., with high degree of expansion, and supplied 

 by a Cornish boiler 22 feet long by 6 feet 6 inches diameter. The 

 consumption of fuel at the trials was found to be 4J lb. per I.H.R 

 Allowing an efficiency of ^54, this is equal to 8*33 lb. per W.H.P. 

 The cost of the pump and engines complete was 1850/. The 

 buildings, culverts, and foundations cost 2725/. ; together, 4575^., 

 equal to i"84/. per acre drained, and 37/. per horse-power of 

 water lifted for the machinery, and 54/. ioj". for the buildings; 

 together, 91/. 10s. per W.H.P. Trials of this pumping machinery 

 were made soon after the erection, steam in the boiler being from 

 30 lb. to 35 lb., and the mean pressure on the piston varying 

 from 14*79 lb. to 17 "02 lb., the engine making 47^ to 54J 

 revolutions, and the lift— that is, the difference of level of water 

 in mouth of inlet culvert and in the outlet at engine-house — varying 

 from 6 feet 2 inches to 10 feet 2 inches. The indicated horse-power 

 varied from 43*6 to 58-8, and the horse-power of water lifted 

 24*07 to 31*67, giving a mean effective result of 53*8 to 55*2 per 

 cent, or allowing one-sixth of indicated horse-power as the resist- 

 ance of the engines, the mean duty of the pump was 67 per cent. 

 The particulars of these two stations are taken from a paper by 

 Mr. W. Anderson in the * Proceedings ' of the Institution of Civil 

 Engineers in Ireland for 1862 (vol. vii.), in which will be found the 

 full details of the trials and drawings of the scoop wheel, &c. Eor 

 the three years 1881 to 1883, the average rainfall at these stations 

 was 40*34 inches. The scoop wheel, which drains 2410 acres^^ 



